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Uses of Radioactivity
Carbon dating enables us to tell how old something is. However, the thing has
to be living, for example a bone. The bone emits beta radiation from a
substance called carbon 14. Depending on how much beta is emitted, we can
tell how many half lives of carbon 14 have passed and this will tell us how old
the bone is. Carbon 14 is found in every living thing including wood, cloth,
paper and bones. The normal carbon 12 is not radioactive, but carbon 14 is.
Tracing and measuring the flow of liquids and gases
For this, we use gamma radiation because it is the most penetrating. An
example of this is sewage travelling to rivers. You can track sewage from each
house/factory and you can identify where the harmful sewage is coming from.
For medical tracing, we use gamma radiation because it is the least ionising-
the least harmful to people. Doctors inject a radioactive substance into your
body and a gamma camera traces the radiation so you can tell for example
which kidney is blocked. Gamma is also used as it is the most penetrating- it
can reach the camera through the ribcage to be traced.
For sterilising, we use gamma radiation because it is the most penetrating- this
allows it to pass through for example a bag of strawberries. This means that
you can seal something that needs to be sterile in a bag and blast it with